KR102245429B1 - Manufacturing device for tube with porous layer for heat and mass transfer and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a manufacturing apparatus, which forms a superlight porous layer for heat and mass transfer on an outer wall of a tube (10) by a solution process, and a manufacturing method for the tube using the same. According to the present invention, the manufacturing apparatus for the tube with the porous layer for heat and mass transfer comprises: a chamber (40) in a bellows structure with a variable inner volume; an inlet (71) placed on an upper end of the chamber (40), into which the tube (10) and a cast (20) inserted to be inserted and engaged with the inside of the chamber (40), and into which a dispersion liquid injected between the tube (10) and the cast (20) is inserted; a sealing unit (70) which seals the inlet (71) when synthesizing the dispersion liquid into a porous layer (30) through a hydrothermal reaction; a mass measuring unit placed on one side of the chamber (40) to measure a change in the mass or a mass change value when the dispersion liquid is injected; a volume calculation unit placed on one side of the chamber (40) to use the mass change value measured by the mass measuring unit or inputted, and to calculate a volume change value of the chamber (40) needed for a hydrothermal reaction of the dispersion liquid; a linear driver (60) which induces an increase/decrease in the volume of the chamber (40) in accordance with the volume change value calculated by the volume calculation unit; a heater (51) placed to cover an outer side of the chamber (40) to increase/decrease the temperature needed for the hydrothermal reaction; and an insulator (50) placed to cover the outer side of the chamber (40) to maintain the proper temperature needed for the hydrothermal reaction.

Description

A tube manufacturing device equipped with a porous layer for heat and mass transfer, and a tube manufacturing method using the same {MANUFACTURING DEVICE FOR TUBE WITH POROUS LAYER FOR HEAT AND MASS TRANSFER AND MANUFACTURING METHOD THEREOF}

The present invention relates to a manufacturing apparatus for forming an ultra-lightweight porous layer excellent in thermal conductivity and specific surface area on an outer wall of a tube by a solution process, and a tube manufacturing method using the same.

In general, a fin-tube heat exchanger is composed of two or more rows of pipes through which refrigerant flows and a plurality of fins arranged perpendicularly to the pipes, and between the refrigerant flowing inside the pipe and the external air passing between the plurality of fins. Heat is radiated or absorbed through heat exchange.

Conventional finned pipes widely used in heat exchangers have very limited specifications such as commercially available pipe diameters due to manufacturing difficulties and cost issues, and therefore, the shape of the finned pipes can be freely adjusted according to operating conditions and system requirements. There was a difficult problem.

In addition, for mass transfer, a mass transfer material is coated on the fin surface or a mass transfer material is filled in the space between the fins.In the former case, the mass transfer is limited to the curved surface, so the capacity is greatly limited, and the latter has excellent capacity, but the material Because the transfer material affects the heat flow around the fin, the fin does not achieve the originally designed performance, and the heat transfer between the mass transfer material and the fin is not smooth, so it is difficult to control mass transfer by heat.

Therefore, in order to solve the above problem, an ultra-lightweight porous layer having excellent thermal conductivity and specific surface area is formed on the outer wall of the tube by a solution process to replace the existing finned tube.

Korean Patent Publication No. 10-2011-0078520

The present invention has been conceived to solve the above problems, and an object of the present invention is to easily manufacture a tube having excellent thermal conductivity and specific surface area by forming an ultra-lightweight porous layer on the outer wall of a tube by a solution process.

The technical problems to be solved by the invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. I will be able to.

Tube manufacturing apparatus provided with a porous layer for heat and mass transfer according to the present invention,

A chamber 40 provided in a bellows structure and having a variable internal volume;

A dispersion liquid provided at the upper end of the chamber 40 and inserted into the space between the tube 10 and the mold 20 into which the tube 10 and the mold 20 are inserted into the chamber 40 Inlet 71 for inserting;

A sealing portion 70 for sealing the injection port 71 when the dispersion is synthesized into the porous layer 30 through a hydrothermal reaction;

A mass measuring unit provided on one side of the chamber 40 and configured to measure a mass change or input a mass change value when the dispersion is injected;

A volume calculation unit provided on one side of the chamber 40 and calculating a volume change value of the chamber 40 required for hydrothermal reaction of the dispersion liquid by using a mass change value measured or input by the mass measurement unit;

A linear actuator 60 for inducing an increase or decrease in the volume of the chamber 40 according to the volume change value calculated by the volume calculation unit;

A heater 51 provided to surround the outside of the chamber 40 to increase or decrease a temperature required for the hydrothermal reaction;

It characterized in that it includes; provided to surround the outside of the chamber 40 to maintain an appropriate temperature required for the hydrothermal reaction.

In addition, the tube manufacturing method using the porous layer manufacturing device for heat and mass transfer,

After coupling the tube 10 and the mold 20, a first step of coupling the tube 10 coupled to the mold 20 to the tube insertion portion 11 provided in the chamber 40;

A second step of injecting a dispersion liquid into the space between the tube 10 and the mold 20, and then sealing the chamber 40 by combining the sealing portion 70 with the chamber 40;

A third step of sensing a mass change of the injected dispersion by a mass measurement unit provided at one side of the chamber 40 or inputting a mass change value of the injected dispersion by a user;

A fourth step of calculating a volume change value of the chamber 40 required for hydrothermal reaction of the dispersion liquid by a volume calculation unit provided at one side of the chamber 40 using the mass change value detected or input in the third step;

When the volume control unit adjusts the size of the linear actuator 60 using the volume change value of the chamber 40 calculated by the volume calculation unit, the bellows structure of the chamber 40 by the linear actuator 60 A fifth step of adjusting the volume of the chamber 40 by being deformed;

A sixth step of synthesizing the porous layer 30 by hydrothermal reaction of the dispersion using the heater 51 and the heat insulating material 50 provided outside the chamber 40;

A seventh step of cleaning the porous layer 30 by removing the mold 20 after removing the sealing part 70;

An eighth step of dissolving an adsorbent in deionized water and impregnating the surface of the porous layer 30; And

It characterized in that it is manufactured by a ninth step of drying the impregnated porous layer 30 and bonding the adsorbent to the porous layer 30.

By means of solving the above problems, the present invention facilitates heat transfer between the surface of the porous layer and the fluid in the tube through high thermal conductivity, and an ultra-lightweight porous layer capable of maximizing material transfer through a large specific surface area through a solution process. Can be formed on the wall of the tube.

In addition, the present invention can be used in fields requiring ultra-lightweight and flexible design, since it is possible to transfer heat as a core heat exchanger and reactor.

In addition, according to the present invention, a volume calculation unit capable of calculating a required chamber volume change in a tube manufacturing apparatus having a porous layer is provided, so that the volume of the chamber can be easily adjusted under a specific temperature condition.

In addition, in order to manufacture a tube having a porous layer, high temperature and high pressure hydrothermal synthesis must be performed when the dispersion to be injected is synthesized into a porous layer. A volume calculation unit is provided so that the process can be effectively carried out in the saturated vapor-liquid state of the dispersion and stable temperature and pressure can be maintained.

1 is a structural diagram showing a tube manufacturing apparatus provided with a porous layer for heat and mass transfer of the present invention.
Figure 2 is a flow chart showing a method of manufacturing a tube provided with a porous layer for heat and mass transfer of the present invention.
3 is a flowchart illustrating a process of preparing a dispersion in the flowchart of FIG. 2 added.
4 is a flowchart showing a process of impregnating the adsorbent and drying the porous layer 30 impregnated with the adsorbent in the flowchart of FIG. 2.
5 is a diagram showing the form in which the porous layer 30 is bonded by removing the mold 20 from the tube 10 in the method of manufacturing a tube provided with a porous layer for heat and mass transfer according to the present invention.
6 is a photograph showing the experimental results of [Comparative Example 1].
7 is a photograph showing the experimental results of [Comparative Example 2].
8 is a photograph showing the experimental results of [Example].

The terms used in the present specification will be briefly described, and the present invention will be described in detail.

Terms used in the present invention have selected general terms that are currently widely used as possible while taking functions of the present invention into consideration, but this may vary according to the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

When a part of the specification is said to “include” a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

Specific matters including the problems to be solved, means for solving the problems, and effects of the present invention are included in the embodiments and drawings to be described below. Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

As shown in Figure 1, the inventors of the tube manufacturing apparatus provided with a porous layer for heat and mass transfer is a chamber 40, an injection port 71, a sealing part 70, a mass measurement part, a volume calculation part, a linear actuator. It consists of 60, a heater 51, and a heat insulating material 50.

First, the chamber 40 is provided in a bellows structure so that the internal volume is variable.

In the present invention, in order to synthesize the dispersion into the porous layer 30, hydrothermal synthesis at high temperature and high pressure must be performed.In the present invention, in order to stably maintain the temperature and pressure, the solvent contained in the dispersion is saturated vapor-liquid state. It is arranged so that the process proceeds. Conventionally, the amount of solution the user inputs is directly adjusted to maintain the pressure stably, but in the present invention, the appropriate volume of the chamber 40 is calculated according to the user's input or detected mass change value, and the As shown in FIG. 1, it is provided in a bellows structure so that the internal volume of the chamber 40 can be easily adjusted.

Meanwhile, a tube insertion part 11 for fixing the tube 10 inserted into the chamber 40 may be further provided at one side inside the chamber 40. That is, the tube 10 is coupled by inserting the tube 10 into the hole provided in the mold 20, and the hole is O-ring, so sealing and bonding are easy. More specifically, as shown in Fig. 1, since the tube 10 is coupled to maintain a space between the outer circumferential surface of the tube 10 and the mold 20, the tube 10 is in the center hole of the mold 20 10) is inserted and combined, and then the tube 10 is inserted into the tube insertion part 11 after bonding with an o-ring. The tube insertion portion 11 is preferably provided with a first tube insertion portion 11a and a second tube insertion portion 11b by being symmetrical at the center to match the diameter of the tube 10.

Next, the injection hole 71 is provided at the upper end of the chamber 40, the tube 10 and the mold 20 fitted into the chamber 40 are inserted, and the tube 10 and the mold (20) Insert the dispersion to be injected into the space between. When the injection port 71 is coupled to the sealing portion 70, the chamber 40 is sealed.

On the other hand, the dispersion is a GNP mixture obtained by mixing PVP (Polyvinyl pyrrolidone), GNP (Graphene nanoplate), and deionized water, potassium hydroxide (KOH) and GO (Graphene oxide) solution, and then the GNP mixture and It is prepared by mixing. However, instead of the GNP (Graphene nanoplate) and GO (Graphene oxide), other thermally conductive nanomaterials including carbon nanotubes, boron nitride nanotubes, and boron nitride nanosheets may be changed or added to be used.

The PVP (Polyvinyl pyrrolidone) is widely used as a reducing agent.

The GNP (Graphene nanoplatelet) is a two-dimensional carbon nanomaterial exfoliated from graphite.

The deionized water refers to pure water in which ions are removed as much as possible through ultrapure distilled water or tertiary distilled water cation or basic ion exchange resin.

The potassium hydroxide (KOH) helps to create a porous structure in the carbon material.

The GO (Graphene Oxide) solution has excellent water-based dispersibility because functional groups including oxygen are attached to the surface of graphene.

After mixing the potassium hydroxide (KOH) and GO (Graphene oxide) solution in the GNP mixture, the dispersion is prepared by mixing with the GNP mixture. At this time, the structure is formed by hydrothermal synthesis only when less than 10 parts by weight of the GNP mixture is mixed with respect to 1 part by weight of the GO (Graphene Oxide) solution, so it is preferable to perform it under the above conditions.

Next, the sealing part 70 seals the injection port 71 in order to synthesize the dispersion into the porous layer 30 through a hydrothermal reaction.

In order to synthesize the dispersion into the porous layer 30, hydrothermal synthesis at high temperature and high pressure must be performed. In the present invention, in order to stably maintain the temperature and pressure, the process is performed in a saturated vapor-liquid state of the solvent contained in the dispersion. The key is to control the mass of the solvent entering the chamber 40 and the volume of the chamber 40 to fall within an appropriate range by sealing the chamber 40 in which hydrothermal synthesis is performed.

Next, the mass measurement unit is provided on one side of the chamber 40 and is provided to measure a mass change or input a mass change value when the dispersion is injected.

In the conventional case, since the control of the mass change according to the injection of the dispersion is controlled by the user, the volume of the chamber 40 is contained within an appropriate range, so that it is difficult to manufacture the porous layer 30 easily.

Accordingly, the present invention is provided to measure the mass change by the mass measuring unit or to calculate it by the user's input for the process temperature set by the user and the injected dispersion.

Next, the volume calculation unit is provided on one side of the chamber 40, and the volume change value of the chamber 40 required for hydrothermal reaction of the dispersion is calculated using the mass change value measured or input by the mass measurement unit. Calculate.

The volume calculation unit calculates the volume change value of the chamber 40 by [Equation 1].

(Where, V _c is the volume value of the chamber 40, m is the mass of the injected dispersion, and v _g is the specific volume of saturated vapor corresponding to the set process temperature).

_{The required volume (V c} ) of the chamber 40 capable of stably maintaining the pressure required for the hydrothermal synthesis is the mass (m) of the dispersion liquid and the specific volume of saturated steam corresponding to the set process temperature (v _g ) It should be less than the product of liver.

_{The specific volume (v g} ) of the saturated steam corresponding to the set process temperature is stored in the database of the pipe manufacturing apparatus provided with a porous layer for heat and mass transfer according to the present invention, depending on the type of solvent to be introduced, or the database is It is desirable to be provided so as to be interlocked with the built-in system.

The bellows of the chamber 40 are deformed by the _{volume change value V c} of the chamber 40 calculated by [Equation 1], so that the volume of the chamber 40 is changed.

On the other hand, the volume ratio of the dispersion liquid injected into the chamber 40 and the chamber 40 is preferably 1:307 (dispersion: chamber 40) or more based on 160° C. of the deionized water. More specifically, the condition of the volume ratio of the dispersion to the chamber 40 is 1:307 (dispersion: chamber 40) is effective when only the temperature of the chamber 40 is controlled as in the present invention. In other words, under the condition of the volume ratio between the dispersion and the chamber 40, hydrothermal synthesis is easily performed at a lower cost by using the chamber 40 that only controls the temperature compared to the chamber 40 that can control the internal pressure to high pressure. It is a suggested condition to proceed. In the volume ratio range, as the solvent (deionized water) in the dispersion becomes a saturated vapor-liquid mixture under a given temperature condition, the pressure increases and maintains up to the saturation pressure of the solvent (deionized water) to achieve a stable reaction.

On the other hand, if the dispersion is put in less than the volume ratio of the above conditions, the solvent (deionized water) in the dispersion becomes superheated vapor under a given temperature condition, and thus it is impossible to reach a high pressure as needed.

to the next. The linear actuator 60 induces an increase or decrease in the volume of the chamber 40 according to the volume change value calculated by the volume calculation unit.

More specifically, as shown in FIG. 1, a bellows structure is applied to the chamber 40 to control the volume of the chamber 40, and the injection port 71 and the sealing portion 70 are provided at the top. And, a linear actuator 60 is provided to adjust the volume of the chamber 40 by being connected to the sealing part 70 and moving linearly. In addition, the linear actuator 60 is connected to a linear motor device to provide power to the linear actuator 60.

Next, the heater 51 is provided to surround the outside of the chamber 40 to increase or decrease the temperature required for the hydrothermal reaction.

Next, the heat insulating material 50 is provided to surround the outside of the chamber 40 to maintain an appropriate temperature required for the hydrothermal reaction.

The method for manufacturing a tube using the apparatus for manufacturing a porous layer for heat and mass transfer according to the present invention is carried out by the following steps, as shown in FIG. 2.

First, in the first step (S10), the tube 10 and the mold 20 are combined, and then the tube 10 coupled to the mold 20 is combined with the tube insertion part 11 provided in the chamber 40. . That is, the tube 10 is coupled by inserting the tube 10 into the hole provided in the mold 20, and the hole is O-ring, so sealing and bonding are easy. More specifically, as shown in Fig. 1, since the tube 10 is coupled to maintain a space between the outer circumferential surface of the tube 10 and the mold 20, the tube 10 is in the center hole of the mold 20 10) is inserted and combined, and then the tube 10 is inserted into the tube insertion part 11 after bonding with an o-ring. The tube insertion portion 11 is preferably provided with a first tube insertion portion 11a and a second tube insertion portion 11b by being symmetrical at the center to match the diameter of the tube 10.

Next, in the second step (S20), after injecting the dispersion into the space between the tube 10 and the mold 20, the sealing part 70 is combined with the chamber 40 to seal the chamber 40. .

The dispersion is a GNP mixture in which PVP (Polyvinyl pyrrolidone), GNP (Graphene nanoplate) and deionized water are mixed, potassium hydroxide (KOH) and GO (Graphene oxide) solution are mixed and then mixed with the GNP mixture. . However, instead of the GNP (Graphene nanoplate) and GO (Graphene oxide), other thermally conductive nanomaterials including carbon nanotubes, boron nitride nanotubes, and boron nitride nanosheets may be changed or added to be used.

More specifically, as shown in Fig. 3, the dispersion is prepared by the following steps.

First, in step 2-1 (S21), polyvinyl pyrrolidone (PVP), graphene nanoplate (GNP), and deionized water are mixed and dispersed with an ultra sonication to prepare a GNP mixture.

The PVP (Polyvinyl pyrrolidone) is widely used as a reducing agent.

The GNP (Graphene nanoplatelet) is a two-dimensional carbon nanomaterial exfoliated from graphite.

The deionized water refers to pure water from which ions are removed as much as possible through ultrapure distilled water or tertiary distillation cation or basic ion exchange resin.

Next, step 2-2 (S22) is to prepare a dispersion by mixing potassium hydroxide (KOH) and GO (Graphene oxide) solution, mixing with the GNP mixture prepared by dispersing, and dispersing with a homogenizer. do.

The potassium hydroxide (KOH) helps to create a porous structure in the carbon material.

The GO (Graphene Oxide) solution has excellent water-based dispersibility because functional groups including oxygen are attached to the surface of graphene.

As described above, the dispersion is preferably carried out under the above conditions because the structure is formed by hydrothermal synthesis only when less than 10 parts by weight of the GNP mixture is mixed with respect to 1 part by weight of the GO (Graphene Oxide) solution.

In order to synthesize the prepared dispersion into the porous layer 30, hydrothermal synthesis at high temperature and high pressure must be performed.In the present invention, in order to stably maintain the temperature and pressure, in the saturated vapor-liquid state of the solvent contained in the dispersion The process is allowed to proceed, and the key is to seal the chamber 40 in which hydrothermal synthesis is performed, so that the mass of the solvent entering the chamber 40 and the volume in the chamber 40 are adjusted to fall within an appropriate range.

Next, in the third step (S30), a mass measurement unit provided at one side of the chamber 40 detects a mass change of the injected dispersion or inputs a mass change value of the injected dispersion by a user.

In the conventional case, since the control of the mass change according to the injection of the dispersion is controlled by the user, the volume of the chamber is within an appropriate range, so that it is difficult to manufacture the porous layer 30 easily.

Accordingly, the present invention is provided to measure the mass change by the mass measuring unit or to calculate it by the user's input for the process temperature set by the user and the injected dispersion.

Next, the fourth step (S40) uses the mass change value detected or input in the third step (S30), and the volume calculation part provided at one side of the chamber 40 is the chamber ( Calculate the volume change value of 40).

The volume calculation unit calculates an appropriate volume value of the chamber 40 by [Equation 1].

[Equation 1]

(Where, V _c is the volume value of the chamber 40, m is the mass of the injected dispersion, and v _g is the specific volume of saturated vapor corresponding to the set process temperature).

_{The required volume (V c} ) of the chamber 40 capable of stably maintaining the pressure required for the hydrothermal synthesis is the mass (m) of the dispersion liquid and the specific volume of saturated steam corresponding to the set process temperature (v _g ) It should be less than the product of liver.

_{The specific volume (v g} ) of the saturated steam corresponding to the set process temperature is stored in the database of the pipe manufacturing apparatus provided with a porous layer for heat and mass transfer according to the present invention, depending on the type of solvent to be introduced, or the database is It is desirable to be provided so as to be interlocked with the built-in system.

The bellows of the chamber 40 are deformed by the _{volume change value V c} of the chamber 40 calculated by [Equation 1], so that the volume of the chamber 40 is changed.

On the other hand, the volume ratio of the dispersion liquid injected into the chamber 40 and the chamber 40 is preferably 1:307 (dispersion: chamber 40) or more based on 160° C. of the deionized water. More specifically, the condition of the volume ratio of the dispersion to the chamber 40 is 1:307 (dispersion: chamber 40) is effective when only the temperature of the chamber 40 is controlled as in the present invention. In other words, under the condition of the volume ratio between the dispersion and the chamber 40, hydrothermal synthesis is easily performed at a lower cost by using the chamber 40 that only controls the temperature compared to the chamber 40 that can control the internal pressure to high pressure. It is a suggested condition to proceed. In the volume ratio range, as the solvent (deionized water) in the dispersion becomes a saturated vapor-liquid mixture under a given temperature condition, the pressure increases and maintains up to the saturation pressure of the solvent (deionized water) to achieve a stable reaction.

On the other hand, if the dispersion is put in less than the volume ratio of the above conditions, the solvent (deionized water) in the dispersion becomes superheated vapor under a given temperature condition, and thus it is impossible to reach a high pressure as needed.

Next, in the fifth step (S50), when the volume control unit adjusts the size of the linear actuator 60 using the volume change value of the chamber 40 calculated by the volume calculation unit, the linear actuator 60 As a result, the bellows structure of the chamber 40 is modified to adjust the volume of the chamber 40.

More specifically, as shown in FIG. 1, a bellows structure is applied to the chamber 40 to control the volume of the chamber 40, and the injection port 71 and the sealing portion 70 are provided at the top. And, a linear actuator 60 is provided to be connected to the sealing part 70 to move linearly and to adjust the volume of the chamber 40. In addition, the linear actuator 60 is connected to a linear motor device to provide power to the linear actuator 60.

Next, in the sixth step (S60), the porous layer 30 is synthesized by hydrothermal reaction of the dispersion using the heater 51 and the heat insulating material 50 provided outside the chamber 40.

Next, in the seventh step (S70), the porous layer 30 is washed by removing the mold 20 after removing the sealing part 70.

5 shows the tube 10 and the mold 20 coupled in the chamber 40 in more detail. In Fig. 5(a) and (b), the tube 10 and the mold 20 are prepared, respectively, and in Fig. 5(c), the tube 10 combined with the mold 20 in the chamber 40 is described above. It is coupled to the tube insertion part (11). In Fig. 5(d), the dispersion is injected into the spaced space between the tube 10 and the mold 20. 5(e) shows the porous layer 30 bonded to the tube 10 by removing the mold 20 in the seventh step S70.

Washing of the porous layer 30 removes the potassium hydroxide (KOH) by putting it in deionized water.

Next, in the eighth step (S80), after washing the porous layer 30 in the seventh step (S70), an adsorbent is dissolved in deionized water, and the surface of the porous layer 30 is impregnated.

More specifically, after washing the porous layer 30 in the seventh step (S70), an adsorbent such as ammonium chloride is dissolved in the deionized water, and the porous layer 30 is impregnated.

Next, in the ninth step (S90), the impregnated porous layer 30 is dried and the adsorbent is bonded to the porous layer 30.

More specifically, in the ninth step (S90), the porous layer 30 after washing and impregnation is lyophilized to obtain the porous layer 30 in which the adsorbent is bonded to the surface around the tube 10 do. In addition, when oven drying is performed instead of the freeze drying, the volume is reduced by about 50% compared to the freeze drying, so it may be selectively performed by the user.

The following shows an example of a tube manufacturing method using the apparatus for manufacturing a porous layer for heat and mass transfer according to the present invention.

1.When synthesizing based on 30 mL of aerogel, 0.1 g of polyvinyl pyrrolidone (PVP) + 2.5 g of GNP (Graphene nanoplate) + 50 mL of Di water were placed in a 100 mL beaker and used for 30 minutes with an ultra sonication Disperse to prepare a GNP mixture.

2. Put 0.7407 g of potassium hydroxide (KOH) + 50 mL of GO (Graphene oxide) solution (10 g/L) into a 100 mL beaker and mix it with the GNP solution dispersed in step 1 to prepare a GO/GNP mixed solution. The GO/GNP mixed solution is dispersed at 4,000 rpm for 1 hour using a homogenizer to prepare a dispersion. At this time, as the most important part in the synthesis, synthesis is possible only when the mass ratio of the GO/GNP is lower than 1/10.

3. After combining the structure of the mold (20) with the tube (10) to fit the gap at the bottom of the mold (20), put the solution in which the GO (Graphene oxide) solution and GNP are dispersed between the structure of the mold (20) and the outer wall of the tube (10) Synthesis was performed at a temperature of 160°C and a pressure of 618.23 kPa for 3 hours. At this time, in order to proceed with hydrothermal synthesis under stable pressure conditions, the volume ratio of the solution and the chamber 40 should be about 1/307 or more.

4. When the structure of the mold 20 is removed after synthesizing for 3 hours, a hydrogel is synthesized around the tube 10. The thus formed hydrogel is put in deionized water for 3 days to remove potassium hydroxide (KOH). After washing, dissolve the adsorbent in deionized water and impregnate it on the hydrogel surface.

5. When the hydrogel after washing and impregnation is freeze-dried at -80°C for 3 days, an aerogel with adsorption material attached to the surface acquires a structure surrounding the outside of the tube 10.

6. In the case of oven drying, the volume is reduced by about 50% compared to the freeze drying at 120℃ for 12 hours.

The following shows examples according to the mixing conditions of the GO (Graphene oxide) solution and the dispersed GNP mixture in the dispersion.

[Comparative Example 1]

The GNP mixture was treated with 50% of the maximum power with an ultra sonication, and the GO (Graphene oxide) solution and the dispersed GNP mixture were dispersed at 8,000 rpm for 30 minutes using a homogenizer. A dispersion is prepared, but prepared by mixing 10 parts by weight of the GNP mixture based on 1 part by weight of the GO (Graphene Oxide) solution.

Thereafter, the solution in which the GO (Graphene oxide) solution and GNP are dispersed is subjected to hydrothermal reaction at a temperature of 160° C. and a pressure of 618.23 kPa for 3 hours, and then dried.

[Comparative Example 2]

The GNP mixture was treated with 70% of the maximum power with an ultra sonication, and the GO (Graphene oxide) solution and the dispersed GNP mixture were dispersed at 8,000 rpm for 30 minutes using a homogenizer. A dispersion is prepared, but prepared by mixing 10 parts by weight of the GNP mixture with respect to 1 part by weight of the GO (Graphene Oxide) solution.

Thereafter, the solution in which the GO (Graphene oxide) solution and GNP are dispersed is subjected to hydrothermal reaction at a temperature of 160° C. and a pressure of 618.23 kPa for 3 hours, and then dried.

[Example]

The GNP mixture was treated with an ultra sonication, and the GO (Graphene oxide) solution and the dispersed GNP mixture were dispersed at 4,000 rpm for 1 hour using a homogenizer to prepare a dispersion, the It is prepared by mixing 5 parts by weight of the GNP mixture based on 1 part by weight of a GO (Graphene Oxide) solution.

Thereafter, the solution in which the GO (Graphene oxide) solution and GNP are dispersed is subjected to hydrothermal reaction at a temperature of 160° C. and a pressure of 618.23 kPa for 3 hours, followed by drying.

The results of the experiments in [Comparative Example] and [Example] above are shown in [Figs. 6] to [Fig. 8].

[Comparative Example 1] and [Comparative Example 2] were tested by mixing 10 parts by weight of the GNP mixture with respect to 1 part by weight of the GO (Graphene Oxide) solution, and differently using the ultrasonic treatment unit (ultra sonication). As shown in [Fig. 6] and [Fig. 7], it can be seen that the porous layer synthesized after drying is formed in the form of a powder.

[Example], unlike [Comparative Example 1], 5 parts by weight of the GNP mixture was mixed with respect to 1 part by weight of the GO (Graphene oxide) solution. Unlike the case of 10 parts by weight of the GNP mixture based on 1 part by weight of the GO (Graphene Oxide) solution, which is the condition of [Comparative Example], it was confirmed that the porous layer according to the [Example] maintained the airgel form.

By means of solving the above problems, the present invention facilitates heat transfer between the surface of the porous layer 30 and the fluid in the tube 10 through high thermal conductivity, and ultra-light porosity capable of maximizing material transfer through a large specific surface area. The layer 30 can be easily formed on the wall of the tube 10 by a solution process.

In addition, the present invention can be used in fields requiring ultra-lightweight and flexible design, since it is possible to transfer heat as a core heat exchanger and reactor.

As described above, it will be appreciated that the above-described technical configuration of the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention by those skilled in the art.

Therefore, the above-described embodiments are to be understood as illustrative and non-limiting in all respects, and the scope of the present invention is indicated by the claims to be described later rather than the detailed description, and the meaning and scope of the claims and the All changes or modifications derived from the equivalent concept should be construed as being included in the scope of the present invention.

10. Coffin
11. Pipe insert
20. Mold
30. Porous layer
40. Chamber
50. Insulation
51. Heater
60. Linear actuator
70. Seal
71. Inlet
S10. Combining the tube (10) and the mold (20)
S20. Sealing the chamber 40 after injecting the dispersion
S21. Preparation of GNP mixed solution
S22. Dispersion preparation
S30. Detecting the mass change value of the dispersion
S40. Chamber 40 volume change value calculation
S50. Chamber 40 volume control
S60. Synthesis of the porous layer 30
S70. Washing the porous layer 30
S80. Sorbent impregnation
S90. Drying the porous layer 30

Claims (13)

A chamber 40 provided in a bellows structure and having a variable internal volume;
A dispersion liquid provided at the upper end of the chamber 40 and inserted into the space between the tube 10 and the mold 20 into which the tube 10 and the mold 20 are inserted into the chamber 40 Inlet 71 for inserting;
A sealing portion 70 for sealing the injection port 71 when the dispersion is synthesized into the porous layer 30 through a hydrothermal reaction;
A mass measuring unit provided on one side of the chamber 40 and configured to measure a mass change or input a mass change value when the dispersion is injected;
A volume calculation unit provided on one side of the chamber 40 and calculating a volume change value of the chamber 40 required for hydrothermal reaction of the dispersion liquid by using a mass change value measured or input by the mass measurement unit;
A linear actuator 60 for inducing an increase or decrease in the volume of the chamber 40 according to the volume change value calculated by the volume calculation unit;
A heater 51 provided to surround the outside of the chamber 40 to increase or decrease a temperature required for the hydrothermal reaction;
An insulating material 50 provided to surround the outside of the chamber 40 to maintain an appropriate temperature required for the hydrothermal reaction;
Tube manufacturing apparatus provided with a porous layer for heat and mass transfer, characterized in that it comprises a.
The method of claim 1,
A tube insertion part 11 provided on one side inside the chamber 40 to fix the tube 10 inserted into the chamber 40; provided with a porous layer for heat and mass transfer, characterized in that further provided Tube making device.
The method of claim 1,
The volume calculation unit is a tube manufacturing apparatus provided with a porous layer for heat and mass transfer, characterized in that calculating the volume change value of the chamber 40 by [Equation 1]:
[Equation 1]

(Where, V _c is the volume value of the chamber 40, m is the mass of the injected dispersion, and v _g is the specific volume of saturated vapor corresponding to the set process temperature).
The method of claim 1,
The dispersion,
It is characterized in that a mixture of potassium hydroxide (KOH) and GO (Graphene oxide) solution in a GNP mixture of PVP (Polyvinyl pyrrolidone), GNP (Graphene nanoplate) and deionized water is mixed with the GNP mixture Tube manufacturing device provided with a porous layer for transferring heat and mass.
The method of claim 4,
Tube manufacturing apparatus provided with a porous layer for heat and mass transfer, characterized in that mixing less than 10 parts by weight of the GNP mixture with respect to 1 part by weight of the GO solution.
The method of claim 1,
The dispersion,
A tube manufacturing apparatus provided with a porous layer for heat and mass transfer, comprising at least one of carbon nanotubes, boron nitride nanotubes, and boron nitride nanosheets.
After coupling the tube 10 and the mold 20, a first step of coupling the tube 10 coupled to the mold 20 to the tube insertion portion 11 provided in the chamber 40;
A second step of injecting a dispersion liquid into the space between the tube 10 and the mold 20, and then sealing the chamber 40 by combining the sealing portion 70 with the chamber 40;
A third step of sensing a mass change of the injected dispersion by a mass measurement unit provided at one side of the chamber 40 or inputting a mass change value of the injected dispersion by a user;
A fourth step of calculating a volume change value of the chamber 40 required for hydrothermal reaction of the dispersion liquid by a volume calculation unit provided at one side of the chamber 40 using the mass change value detected or input in the third step;
When the volume control unit adjusts the size of the linear actuator 60 using the volume change value of the chamber 40 calculated by the volume calculation unit, the bellows structure of the chamber 40 by the linear actuator 60 A fifth step of adjusting the volume of the chamber 40 by being deformed;
A sixth step of synthesizing the porous layer 30 by hydrothermal reaction of the dispersion using the heater 51 and the heat insulating material 50 provided outside the chamber 40;
A seventh step of cleaning the porous layer 30 by removing the mold 20 after removing the sealing part 70;
Tube manufacturing method using a porous layer manufacturing apparatus for heat and mass transfer, characterized in that manufactured by.
The method of claim 7,
Tube manufacturing method using a porous layer manufacturing apparatus for heat and mass transfer, characterized in that the volume calculation unit calculates an appropriate volume value of the chamber 40 by [Equation 1]:
[Equation 1]

(Where, V _c is the volume value of the chamber 40, m is the mass of the injected dispersion, and v _g is the specific volume of saturated vapor corresponding to the set process temperature).
The method of claim 7,
The dispersion,
Heat and mass transfer, characterized in that the mixture of GNP (Graphene nanoplate) and deionized water is mixed with potassium hydroxide (KOH) and GO (Graphene oxide) solution, and then mixed with the GNP mixture. Pipe fabrication method using a porous layer fabrication device for.
The method of claim 7,
The dispersion,
A 2-1 step of preparing a GNP mixture by mixing polyvinyl pyrrolidone (PVP), graphene nanoplate (GNP), and deionized water and dispersing it with an ultra sonication;
A second step of preparing a dispersion by mixing potassium hydroxide (KOH) and GO (Graphene oxide) solution, mixing with the GNP mixture prepared by dispersing, and dispersing with a homogenizer;
Tube manufacturing method using a porous layer manufacturing apparatus for heat and mass transfer, characterized in that manufactured by.
The method of claim 7,
After washing the porous layer 30 in the seventh step,
An eighth step of dissolving an adsorbent in deionized water and impregnating the surface of the porous layer 30; And
A method for manufacturing a tube using a porous layer manufacturing apparatus for heat and mass transfer, characterized in that produced by a ninth step of drying the impregnated porous layer 30 and bonding the adsorbent to the porous layer 30 .
The method of claim 7,
In the second step, the dispersion,
Tube manufacturing method using a porous layer manufacturing apparatus for heat and mass transfer, characterized in that less than 10 parts by weight of the dispersed GNP mixture per 1 part by weight of the GO (Graphene Oxide) solution.
The method of claim 7,
The dispersion,
A method for manufacturing a tube using a porous layer manufacturing apparatus for heat and mass transfer, comprising at least one of carbon nanotubes, boron nitride nanotubes, and boron nitride nanosheets.

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